DOYLESTOWN, Pa. (CBS) – This coming Saturday, October 29th, is “National Drug Take-Back Day,” encouraging people with expired or unneeded prescription medications to dispose of them safely.

Experts point out that throwing pharmaceuticals in the trash or down the toilet can contaminate landfills and wastewater with biologically active chemicals.

Pennsylvania and Delaware will have 380 drop-off sites, and one local county is leading the way with 15 permanent boxes already.

Bucks County has had prescription drop-off boxes set up for several months, and many times those boxes are filled to overflowing. District attorney David Heckler says the public response has been tremendous, and the national day is another way of drawing attention to the effort.

“It has the (additional) advantage of keeping these substances that may be subject to abuse out of the hands of those who might sell them on the street or use them themselves,” he said.

Heckler says the most abused prescription is Oxycontin, but all painkillers are potentially dangerous, especially to young people.

He says painkillers and opiates are being abused by young people today more than what are considered “traditional” drugs like cocaine and heroin.

Many of the drop-off sites on Saturday will be at local police departments.